Veliger Sampling
Three times in the open water season, at locations strategically identified by the Sauk River Watershed District, volunteers help to monitor the various lakes in the watershed for veligers...the microscopic young of zebra mussels.
TOP LEFT: The nets, called "plankton nets" are dropped to just above the bottom of the lake at each of the identified locations. In Sauk Lake, there are 5 locations north of the bridge, and 3 locations south of the bridge.
TOP MIDDLE: Drawing the nets up, everything floating will be caught in the net and will drop down into the collection cup at the bottom.
TOP RIGHT: All of the water is vigorously shaken out through filters on the sides of the collection cup.
BOTTOM LEFT: That which is left, is transferred to a specimen container, preserved with 99% alcohol, and delivered to the proper folks to do testing for the existence of "veligers".
Thus far, though zebra mussels exist upstream in the Sauk River watershed (Osakis, Guernsey) and downstream (Birch and Lake Sylvia) they have not been discovered in Big Sauk Lake.
TOP LEFT: The nets, called "plankton nets" are dropped to just above the bottom of the lake at each of the identified locations. In Sauk Lake, there are 5 locations north of the bridge, and 3 locations south of the bridge.
TOP MIDDLE: Drawing the nets up, everything floating will be caught in the net and will drop down into the collection cup at the bottom.
TOP RIGHT: All of the water is vigorously shaken out through filters on the sides of the collection cup.
BOTTOM LEFT: That which is left, is transferred to a specimen container, preserved with 99% alcohol, and delivered to the proper folks to do testing for the existence of "veligers".
Thus far, though zebra mussels exist upstream in the Sauk River watershed (Osakis, Guernsey) and downstream (Birch and Lake Sylvia) they have not been discovered in Big Sauk Lake.
